"Bluefin tuna is near ecological and commercial extinction," said Sergi Tudela, head of the fisheries program at WWF in Barcelona, Spain.

An annual quota set by the International Commission for the Conservation of Atlantic Tuna (ICCAT) restricts tuna catches across the Mediterranean to 32,000 tons (29,000 metric tons).

But WWF estimates that the quota is being violated by about 50 percent and that real catches of bluefin tuna are around 50,000 tons (45,000 metric tons).

The main offenders are France, Libya, and Turkey, the organization says.

"The deliberate underreporting [of tuna fishing] by certain [countries], like France, and the impunity with which most industrial fleets are contravening the international legislation points to a situation of virtually unregulated fishing," Tudela said.

Disappearing Act

According to the WWF report, traditional tuna-trap fishermen in the Gibraltar Strait between Spain and Morocco have in the last three years caught 80 percent less fish than they did in the late 1990s.

Ubiquitous tuna schools in the waters off the Croatian coast in the Adriatic Sea were once a tourist attraction. Today no wild tuna is to be found.

One problem, Tudela says, is that the Mediterranean Sea now supports fishing over its entire surface. This means there is no refuge for bluefin tuna to spawn.